contralateral comparison of three excimer laser systems in performing lasik

Conditions: Myopia; Astigmatism

Summary: the purpose of this study is to compare lasik outcomes using the wavelight allegretto wave™ wavefront guided or optimized excimer laser treatment with the amo/visx customvue™ and the ladarvision 4000 excimer laser treatment. standard refractive outcomes such as uncorrected and best corrected visual acuity, and intended vs. achieved postoperative refractions will be evaluated; in addition, high order optical aberrations, contrast sensitivity, and topography will be measured.

the primary objective of this study is to compare wavelight allegretto wave™ wavefront guided or optimized excimer laser treatment with the amo/visx customvue™ and the ladarvision 4000 excimer laser treatment using both subjective and objective outcome measures. this comparison will be made between fellow eyes of the same patient following excimer laser ablation using the wavelight allegretto wave™ excimer laser system in one eye and the amo/visx customvue™ or the ladarvision 4000 excimer laser in the contralateral eye .

Eligibility criteria:
inclusion criteria: * subjects who have up to -7.00d of spherical equivalent myopia or myopia with astigmatism, with up to -7.00d of spherical component and up to 3.00 d of astigmatic component at the spectacle plane in both eyes. * subjects must have a stable refraction as documented by previous clinical records. spherical equivalent has not progressed at a rate of more than 0.50d per year prior to the baseline examination in both eyes or as documented by clinical judgment by the investigator. * subjects who wear contact lenses must discontinue wear at least 3 days for soft and at least 3 weeks for rgp prior to the preoperative evaluation or surgery, in either eye. * subjects must have visual acuity correctable to at least 20/20 in both eyes. * subjects must be at least 18 years of age. * subjects must be willing and able to return for scheduled follow up examinations for twelve months after lasik surgery. * subjects must sign and be given a copy of the written informed consent form. exclusion criteria: * subjects for whom both eyes do not meet all inclusion criteria and either eye meets any exclusion criteria. * subjects for whom the combination of their baseline corneal thickness and the planned operative parameters for the lasik procedure would result in less than 250 microns of remaining posterior corneal thickness below the flap postoperatively in either eye. * eyes for which the baseline standard manifest refraction exhibits greater than 1.00d more minus in sphere power, or a difference of greater than 0.75 d in cylinder power. * subjects desiring spherical under correction in one eye (i.e. no monovision correction is permitted). * subjects for whom the preoperative assessment of the ocular topography and /or aberrations indicates that either eye is not a suitable candidate for lasik vision correction procedure. examples include frank or forme frust keratoconus, corneal warpage, pellucid marginal degeneration, etc. * subjects with clinically significant dry eye syndrome or clinically significant blepharitis in either eye. * subjects with anterior segment pathology, including clinically significant cataracts or corneal scarring or neovascularization in either eye. * subjects with residual, recurrent, active ocular or eyelid disease, including any corneal abnormality (specifically, recurrent corneal erosion, severe basement membrane disease) in either eye. * subjects with ophthalmoscopic signs of progressive or unstable myopia or keratoconus (or keratoconus suspect) in either eye. * subjects with unstable (distorted/not clear) corneal mires on central keratometry in either eye. * subjects who have undergone previous intraocular or corneal surgery of any kind, including any type of surgery for either refractive or therapeutic purposes in either eye. * subjects who have a history of herpes zoster or herpes simplex keratitis. * subjects on chronic systemic corticosteroid or other immunosuppressive therapy that may affect wound healing, any immunocompromised subjects, and subjects with clinically significant atopic disease, connective tissue disease, or diabetes. * subjects with a history of steroid-responsive rise in intraocular pressure, glaucoma, or preoperative intraocular pressure\>23 mm hg in either eye. * subjects with macular pathology in either eye. * subjects who are pregnant, lactating, or planning to be pregnant during the course of the study. * subjects with known sensitivity to planned study concomitant medications. * subjects participating in any other ophthalmic drug or device clinical trial during the time of this clinical investigation.

Keywords: myopia lasik astigmatism laser vision correction excimer laser